Biodegradable quaternary ammonium salts such as N,N-di(tallowoyloxyethyl)-N,N,-dimethylammonium chloride and 1,2-ditallowyloxy-3-trimethylammonio propane chloride have been developed as described in U.S. Pat. Nos. 4,137,180; 4,767,547 and 4,789,491. Many of these molecules break down to a transitory 3-monoester quaternary which has been observed to break down readily and have no significant impact on the environment. Water, J. et al. "A New Rinse conditioner Active with Improved Environmental Properties," Tenside Surf. Det. 28 (1991) p. 460-468.
Fabric conditioning molecules which degrade to the starting materials which are naturally occuring molecules offer another attractive material for producing fabric conditioners.